A variety of fan systems have been made and used over the years in a variety of contexts. For instance, various ceiling fans are disclosed in U.S. Pat. No. 7,284,960, entitled “Fan Blades,” issued Oct. 23, 2007; U.S. Pat. No. 6,244,821, entitled “Low Speed Cooling Fan,” issued Jun. 12, 2001; U.S. Pat. No. 6,939,108, entitled “Cooling Fan with Reinforced Blade,” issued Sep. 6, 2005; and U.S. Pat. No. D607,988, entitled “Ceiling Fan,” issued Jan. 12, 2010. The disclosures of each of those U.S. patents are incorporated by reference herein. Additional exemplary fans are disclosed in U.S. Pub. No. 2008/0008596, entitled “Fan Blades,” published Jan. 10, 2008; U.S. Pub. No. 2009/0208333, entitled “Ceiling Fan System with Brushless Motor,” published Aug. 20, 2009; and U.S. patent application Ser. No. 12/773,094, entitled “Ceiling Fan with Variable Blade Pitch and Variable Speed Control,” filed May 4, 2010, the disclosures of which are also incorporated by reference herein. It should be understood that teachings herein may be incorporated into any of the fans described in any of the above-referenced patents, publications, or patent applications.
A fan blade may be formed of several components that permit its configuration to be changed in a modular fashion. Examples of modular fan blades are disclosed in U.S. Pub. No. 2010/0104461, entitled “Multi-Part Modular Airfoil Section and Method of Attachment between Parts,” published Apr. 29, 2010, the disclosure of which is incorporated by reference herein. A fan blade or airfoil may also include additional reinforcement relative to the hub of the fan. Merely exemplary fan blade reinforcement components and configurations are described in U.S. Provisional Patent App. No. 61/369,953, entitled “Fan Blade Retention System,” filed Aug. 2, 2010, the disclosure of which is incorporated by reference herein. Alternatively, any other suitable type of component or feature may be used to reinforce the coupling of a fan blade with a fan hub; or such components or features may simply be omitted.
The outer tip of a fan blade or airfoil may be finished by the addition of an aerodynamic tip or winglet. Merely exemplary winglets are described in U.S. Pat. No. 7,252,478, entitled “Fan Blade Modifications,” issued Aug. 7, 2007, the disclosure of which is incorporated by reference herein. Additional winglets are described in U.S. Pub. No. 2008/0014090, entitled “Cuffed Fan Blade Modifications,” published Jan. 17, 2008, filed Sep. 25, 2007, the disclosure of which is incorporated by reference herein. Still other exemplary winglets are described in U.S. Design Pat. No. D587,799, entitled “Winglet for a Fan Blade,” issued Mar. 3, 2009, the disclosure of which is incorporated by reference herein. In some settings, such winglets may interrupt the outward flow of air at the tip of a fan blade, redirecting the flow to cause the air to pass over the fan blade in a perpendicular direction, and also ensuring that the entire air stream exits over the trailing edge of the fan blade and reducing tip vortex formation. In some settings, this may result in increased efficiency in operation in the region of the tip of the fan blade. In other variations, an angled extension may be added to a fan blade or airfoil, such as the angled airfoil extensions described in U.S. Pub. No. 2008/0213097, entitled “Angled Airfoil Extension for Fan Blade,” published Sep. 4, 2008, the disclosure of which is incorporated by reference herein. Other suitable structures that may be associated with an outer tip of an airfoil or fan blade will be apparent to those of ordinary skill in the art. Alternatively, the outer tip of an airfoil or fan blade may be simply closed (e.g., with a cap or otherwise, etc.), or may lack any similar structure at all.
The interface of a fan blade and a fan hub may also be provided in a variety of ways. For instance, an interface component is described in U.S. Pub. No. 2009/0081045, entitled “Aerodynamic Interface Component for Fan Blade,” published Mar. 26, 2009, the disclosure of which is incorporated by reference herein. Alternatively, the interface of a fan blade and a fan hub may include any other component or components, or may lack any similar structure at all.
Fans may also include a variety of mounting structures. For instance, a fan mounting structure is disclosed in U.S. Pub. No. 2009/0072108, entitled “Ceiling Fan with Angled Mounting,” published Mar. 19, 2009, the disclosure of which is incorporated herein. Of course, a fan need not be mounted to a ceiling or other overhead structure, and instead may be mounted to a wall or to the ground. For instance, a fan may be supported on the top of a post that extends upwardly from the ground. Alternatively, any other suitable mounting structures and/or mounting techniques may be used in conjunction with embodiments described herein.
It should also be understood that a fan may include sensors or other features that are used to control, at least in part, operation of a fan system. For instance, such fan systems are disclosed in U.S. Pub. No. 2009/0097975, entitled “Ceiling Fan with Concentric Stationary Tube and Power-Down Features,” published Apr. 16, 2009, the disclosure of which is incorporated by reference herein; U.S. Pub. No. 2009/0162197, entitled “Automatic Control System and Method to Minimize Oscillation in Ceiling Fans,” published Jun. 25, 2009, the disclosure of which is incorporated by reference herein; WIPO Pub. No. WO/2009/100052, entitled “Automatic Control System for Ceiling Fan Based on Temperature Differentials,” published Aug. 13, 2009, the disclosure of which is incorporated by reference herein; and U.S. Provisional Patent App. No. 61/165,582, entitled “Fan with Impact Avoidance System Using Infrared,” filed Apr. 1, 2009, the disclosure of which is incorporated by reference herein. Alternatively, any other suitable control systems/features may be used in conjunction with embodiments described herein.
In some settings, it may be desirable to replicate or approximate the function of a winglet in a component that may be located at a position on a fan blade other than at the free end of the fan blade. Such a component may provide an effect on fan efficiency similar to the effect provided by a winglet, albeit at one or more additional regions of the fan blade. In particular, such a component or accessory may serve as an aerodynamic guide or air fence, interrupting slippage of air along the length or longitudinal axis of the fan blade; and redirecting the air flow to a direction perpendicular to the longitudinal axis of the fan blade, above and/or below the fan blade.
While a variety of components have been included with fans and fan systems, it is believed that no one prior to the inventors has made or used the invention described herein.
The drawings are not intended to be limiting in any way, and it is contemplated that various embodiments of the invention may be carried out in a variety of other ways, including those not necessarily depicted in the drawings. The accompanying drawings incorporated in and forming a part of the specification illustrate several aspects of the present invention, and together with the description serve to explain the principles of the invention; it being understood, however, that this invention is not limited to the precise arrangements shown.